[.net] Communication between components

1) Make an event handler that processes the button click.

To make an event handler double click the button its also available in the properties toolbar.

2) In the event handler update the text of the textbox.

That's rather difficult since the button is on a component, and the textbox is on the form. The form also houses the component.

_Form_________________|                     || [__-Textbox__]      ||                     || |----------------|  || |component       |  || |                |  || |    [Button]    |  || |                |  || |                |  || |----------------|  |_______________________

You would need to have give the component a delegate member that could be set when you initialize the form. In your case, the delegate would reference a "set text" method on the form. When the button is clicked, the delegate would be called and your text would be updated.

Why exactly are you designing your UI this way? Components are supposed to be self-contained and reusable, so you should be very careful when creating dependencies with external data (like your textbox).

- Mike

I am attempting to create an onscreen keyboard, for use in multiple forms.

If you have a better suggestion, I am open to new ideas.

Clicky

So I would do it like

component has a public event KeyClicked(String key)

And each button click would go to a button click event that calls that public one

OnButtonClick()
Button x = sender as Button;
OnKeyClicked(x.text);

Then in your form you just capture it

component myComponent = new component;
myComponent.KeyClicked += new KeyClick(HandleIt);

void HandleIt(String key)
this.textbox1.text += key;

Quote:

Original post by Justaddwater So I would do it like component has a public event KeyClicked(String key) And each button click would go to a button click event that calls that public one OnButtonClick() Button x = sender as Button; OnKeyClicked(x.text); Then in your form you just capture it component myComponent = new component; myComponent.KeyClicked += new KeyClick(HandleIt); void HandleIt(String key) this.textbox1.text += key;

This sounds like its down the right path, but I have never created a new event - how exactly would I go about doing this?

Your component class

namespace Whatev{    public delegate void KeyButtonPush(String button);    public partial class HandyThing : UserControl    {        public event KeyButtonPush ButtonPushThing;        void MyKeyButtonPush(string button)        {            if (ButtonPushThing != null)            {                ButtonPushThing(button);            }        }        public HandyThing()        {            InitializeComponent();        }        private void button2_Click(object sender, EventArgs e)        {            Button x = sender as Button;            MyKeyButtonPush(x.Text);        }    }}

Then in your main application you add the following to get it...

namespace Whatev{    public partial class Form1 : Form    {        public Form1()        {            InitializeComponent();            HandyThing handyThing = new HandyThing();            handyThing.Dock = Dockstyle.Fill;            Controls.Add(handyThing);            handyThing.ButtonPushThing += new KeyButtonPush(handyThing_ButtonPushThing);        }        void handyThing_ButtonPushThing(string button)        {            MessageBox.Show(button);        }    }}

Quote:

Original post by Justaddwater ...code

This almost worked, but for whatever reason - it will display the message box twice (or any code I insert there will execute twice)...and I am not double clicking the button or anything.

Any ideas?

You use the exact code? I tested it in VS 2005 and it works fine.

That being said, I assume you broke it down a little different, make sure there is no way the event handler is being wired up more then once.



That is most likly the culprit...